Ammonium Nitrate Explosions, Fires and

Texas City Disaster. See under Ammonium Nitrate Explosions, Fires and Hazards in Vol 1, A359-L to A362-L... 

Ammonium Nitrate Dynamite (AND) (American and European Types) A355 to A356 Ammonium Nitrate Explosions, Fires and Hazards A357 to A363 Ammonium Nitrate Explosives of Spencer Chemical Co A354 (table)... 

R.W. Van Dolah et al, "Explosion Hazards of Ammonium Nitrate under Fire Exposure , USBurMinesReptInvest No 6773, 79pp(1966) CA 65, 564(1966) [The conditions under which AN and its systems may explode when subjected to intense fire exposure (never previously defined) were investigated at the US-BurMines. The intrinsic sensitivity was studied by card-gap techniques. Fertilizer-grade AN was detonated, but at RT very large chges and strong expl donors were required. Prills coated... 

On April 17, 2013, an ammonium nitrate explosion at the West Fertilizer Company storage and distribution facility in West, Texas, killed at least 15 people—the majority of whom were firefighters responding to a fire at the facility—and injured over 160 others. 

Safety Considerations. Ammonium nitrate can be considered a safe material if treated and handled properly. Potential hazards include those associated with fire, decomposition accompanied by generation of toxic fumes, and explosion. 

In the other method, particularly popular in Germany, the ammonium nitrate is replaced by an equimolar mixture of ammonium chloride and potassium or sodium nitrate. The reaction between the salts, which gives potassium or sodium chloride and ammonium nitrate or its decomposition products, is relatively slow and does not occur to a marked extent when the explosive is fired in an unconfined condition. This method of working is particularly effective in reducing the power of an explosive in the unconfined condition. Used alone it has not proved popular in Britain, because of the low power which tends to be developed under practical firing conditions. Moreover, the finely divided sodium chloride smoke which is produced by the explosive tends to be unpleasant for the miners. 

For civilian aircraft the facility for rapid starting is not important and cartridge operation is not often employed, particularly because it involves storing and handling explosives, even though the hazards of these explosives are those of fire and not of detonation. For military purposes, however, particularly for fighter aircraft which are best scattered on an airfield, a rapid start is of considerable importance. Therefore cartridge operated starters are much used for these aeroplanes. In Britain, development has been essentially with propellants based on ballistite, namely double base propellants of the solventless type, whereas in the United States composite propellants based on ammonium nitrate have proved more popular. 

The military explosives RDX and HMX are manufactured from the 3 components using the Bachman process. Some of the possible mixtures may lead to fires in open vessels and explosions under confinement, and the exothermic and other effects (some calculated by the CHETAH program) for a wide range of mixtures are presented as ternary diagrams. It was also found that acetic anhydride layered onto solutions of ammonium nitrate in nitric acid exploded, owing to formation of acetyl nitrate. 

Decomposition of a 70% nitric acid-ammonium nitrate slurry explosive led to overflow, contact with wood and a fire. This spread to detonators, which initiated detonation of the slurry. 

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